1. Field of the Invention
Embodiments of the present invention relate generally to flat panel displays. More specifically, embodiments of the present invention relate to a backlight unit and a liquid crystal display including the same.
2. Description of the Prior Art
A liquid crystal display is currently one popular information display technology. The liquid crystal display displays information by employing liquid crystals, which are inserted between two glass substrates, and which emit light through application of power to electrodes positioned on upper and lower portions of the glass substrates.
The liquid crystal display is a light receiving device which is not self-luminous and thus displays an image through adjustment of permeability of light that is input from an external source, and thus requires a separate device for irradiating its liquid crystal panel with light. This is typically a backlight unit.
Recently, a light emitting diode (LED) array has been employed as a light source for a backlight unit of a liquid crystal display. The LED is a semiconductor light emitting element that emits light when current flows through the LED. Since the LED has the advantages of long lifespan, low power consumption, rapid response speed, and superior initial driving characteristics, it has been widely used as an illumination device, a billboard, and a backlight unit of a display device, and its application fields have been gradually extended.
In the case of using an LED light source, quantum dots are used to heighten color purity. The quantum dots emit light as unsteady electrons are transited from a conduction band to a valence band, and have the characteristics that wavelengths of emitted light differ depending on the size of particles used, even if those particles are all made of the same material. Since the quantum dots generate light of shorter wavelength as the size of the quantum dots becomes smaller, light of a desired wavelength range can be obtained through adjustment of the size of the quantum dots.
Accordingly, recent efforts have focused on implementation of white light having wide color gamut from light generated from an LED using quantum dots.